Electric ignition of explosives.



R. MILLER.

ELECTRIC IGNITION 0F EXPLOSIVES.

APPLICATION FILED 1AN.21. 1916.

35,993, Patented Aug. 7, 191?.

ROBERT MILLEIB, OF NEW YORK, N. Y.

ELECTRIC IGNITION OF EXPLOSIVES.

Specification of Letters Patent.

Application filed January 21, 1916. Serial No. 73,346.

.gines, blasting machines, and the like. In

certam types of these various mechanisms it is extremely desirable for the most eflicient results to ignite these explosive mixtures simultaneously at two or more places. The

. object of my invention, therefore, is to accomplish this result in a simple, effective, reliable, and inexpensive manner.

My device is intended for use with the usual means of producing a high tension spark, such for example, as an ordinary induction coil or magneto, and the usual spark plugs. The invention, therefore, comprises means for attaining the object in view, and particularly includes numerous details and peculiarities in the construction, arrangement, and combination of the various parts, substantially as will be hereinafter described and then more particularly pointed out in the claims.

In the accompanying drawing illustrating my invention, the single figure shown is a vertical section through the end of the cylinder of a gas engine equipped with my device.

1 denotes the cylinder of such an engine. In it the usual high tension spark plug 2 is inserted which may be of any esired kind. A high tension conductor 3 leads from the secondary circuit of a magneto or induction coil to the spark plug 2. 4 denotes a second or extra spark (plug, which by means of a conductor 5 an a condenser 6 is placed in inductive relation to the spark lug 2. 7 7 denote valves in the cylinder eads which may be arrangs'd in any desired and ordinary way. T e condenser 6 is preferably of the Leyden jar type. The operation of the whole device may be described as follows: When the high tension current from the secondary windm of the induction coil or magneto is sent into the conductor 3, it will, instead of jumping the charge.

gap of the spark plug 2, innnediatel charge one side of the condenser 6. This 0 arge in turn tends to induce a charge, of opposite olarity on the other side of'the condenser 6.

en the electrostatic stress due to this action is high enough to break down the resistance of the air gap in plug 4, a spark passes at this gap as this surface becomes charged. The primary charge of-the condenser having now reached a high potential, it discharges through the gap of plug 2. The induced charge in the condenser ,m turn discharges through plug 4 and equilibrium becomes established. This charging and discharging takes place with such enormous rapidity that ignition of the explosive mixture is efl'ected at the two spark plugs gaps.

simultaneously. I Although I have shown these arts arranged in their relation to the cy inder of a gas engine, yet it should be understood that I have done this sim ly as a specimen illustration of one way of applying the invention for actual use and that I am by no means to be restricted thereto, but am at liberty to make all the changes necessary to adapt the improvements for use in other devices, and I, therefore, reserve the liberty of making such changes as experience may suggest to be necessary and for applying the invention for various purposes.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a system of spark ignition apparatus for firin a combustible mixture, the combination 0 a high tension conductor, a condenser charged t ereby, and a plurality of ignition points within the combustible mixture, which points are operated by an induced charge.

2. In a device for electrically igniting explosive mixtures, condensing means char ed high tension current, sparkingl devices disposed within the mixture whic devices are operated simultaneously by the induced 3. In the electric i 'tion of explosives, the combination of a high tension conductor a condenser, one side of which is charged thereby, while the other side is in turn inductively charged, an i 'tion device operated by said induced c arge, and another i tion device operated by the primary c arge of the condenser.

4. In a system of spark ignition apparatenteu Aug. *7, 1917. I

'ratus for firing a combustible mixture, comprising in combination, a high tension 01!- cuit sparking plugs disposed within the combustible mixture and in such high tension circuit, and condensing means placed between sald sparking lugs.

5. A system of spar ignition apparatus 6. The herem-described method of ignition at multiple points, consisting in charging a condenser with a high tension current,

1,asa,oos

and passing current induced by said high tension current to a plurality of ignition evices within the com ustible mixture in such a manner that'the said devices may be operated by the induced charge.

7. The herein-described methodof electrically i ting explosive mixture, which consists o chargingi a condenser with a high tension current, osin a plurality of sparking devices wit in t e explosive mixture, and causing said devices to be operated simultaneously by the induced charge from the condenser.

In testimony whereof I aflix my signature.

ROBERT MILLER. 

